A wide variety of stands are utilized in the entertainment industry, as well as in other fields, for supporting microphones (xe2x80x9cmicsxe2x80x9d), speakers, lighting, musical instruments, music scores, etc. The industry standard for a mic stand employs a round, sand-cast base that measures about 10 inches in diameter and weighs about six pounds, with which a shaft is threadably assembled. The shaft will usually consist of two telescoping tubular sections operatively interengaged by a center clutch for permitting height adjustment, the most widely used form of clutch being operated by rotation of a collar attached to the lower shaft section.
The conventional round-base stands suffer from a number of deficiencies, primary amongst which is inadequate stability. Because these stands usually employ a number of discrete, floor-contacting elements distributed under the edge of the base, downward force (e.g., by users stepping on the base of the stand), particularly in areas lying outwardly of the secants between adjacent contact elements, will tend to cause the stand to tip. Also, the upper marginal structure surrounding the base is typically of such form that downward forces tend to produce pivotal moments, thereby contributing to instability, and the relatively high profile and uniform metal thickness in the conventional base structure do not afford an optimal center of gravity or weight distribution.
Exacerbating these factors is the preference of many performers to stand in close proximity to a supported microphone. Not only does the standard round base inhibit such close approach, by not readily accommodating the user""s feet, but it also prevents the close lateral stacking of a number of microphones (or other equipment) that is frequently desired on stage and in the studio.
The threading features, and indeed, the basic screw-together nature of the conventional stand assembly, also give rise to difficulties. First of all, because the clutch on the shaft is commonly designed for release by rotating a collar (invariably, in the same direction as that in which the shaft is unscrewed from the base), there is a chronic tendency for loosening to occur during normal use. Due to the fineness of the threads utilized, moreover, not only is interengagement of the shaft and the base difficult and time-consuming (both because it is hard to properly align the parts from a standing position with the base resting on the floor, and also because many revolutions of the shaft are required for full tightening), but furthermore the threads themselves are frequently damaged due to crossing or misalignment, or simple physical impact.
Accordingly, it is a broad object of the present invention to provide a novel base for a stand, and a novel stand assembly utilizing such a base, wherein a high degree of stability is afforded and close approach and facile lateral stacking are enabled.
It is also an object of the invention to provide such a base and stand assembly wherein assembly and disassembly are relatively quick and easy, and wherein tendencies for damage to occur to component parts, and especially to thread elements, are significantly reduced.
It has now been found that certain of the foregoing and related objects of the invention are attained by the provision of a ground-engaging base comprised of a low-profile base member of modified hexagonal peripheral configuration. The base member is symmetrical about each of three axes mutually angularly spaced by 120xc2x0, and the peripheral configuration is comprised of three longer edges, of a first length, and three interposed shorter edges, of a second length, one of the longer edges and an opposing shorter edge lying substantially perpendicular to each of the axes.
The ratio of the first length to the second length (i.e., of the longer and shorter edges, respectively) should be about 2.5:1 to 4.5:1, preferably about 3:1 to 4:1, and most desirably about 3.5:1. In most instances a multiplicity of ground-engaging elements will project downwardly beneath a bottom plane of the base, one of which elements is disposed substantially at each of the apices at which the peripheral edges intersect. Although a discrete piece may provide each ground-engaging element, preferably an elongate foot piece will extend along the periphery of the base member, adjacent each of the shorter edges, to provide a pair of such elements.
The upper marginal structure extending along each of the longer peripheral edges (and usually along the shorter edges as well) will beneficially be inwardly bevelled to minimize the likelihood that downward force thereupon will cause tipping of the base. The topside of a web portion of the base member (i.e., the interior portion, surrounded by the peripheral edges and the marginal structure) will advantageously be formed with a raised ridge structure extending outwardly, along each of the three 120xc2x0 angularly spaced axes, from adjacent the intersection of the axes to a location proximate the corresponding one of the shorter edges. Such ridge structures will desirably be of generally inverted V-shaped cross section and tapered in the outward direction, thereby adding to the mass of the base member and providing a weight distribution that contributes substantially to stability.
Other objects of the invention are attained by the provision of a stand assembly comprised of a ground-engaging base, as herein described, a shaft, and means for attaching the shaft to the base. The means for attaching will generally take the form of a normally upwardly opening aperture (i.e., an aperture that opens upwardly when the base is resting on the ground) defined in the base member substantially at the intersection of the 120xc2x0 axes, in combination with an end portion of the shaft that is dimensioned and configured for engagement within the aperture.
In one preferred embodiment, the end portion of the shaft and the sidewall of the base member aperture will be matingly threaded with a pitch that provides no more than four, and more advantageously fewer than three, threads per inch. The threaded end portion of the shaft will most desirably be provided on a solid metal plug affixed to a length of metal tubing comprising the shaft. In especially preferred embodiments the stand assembly will include anti-rotation means, such as a foot-operated ratchet mechanism, for releasably interengaging the shaft against unscrewing from the base member.
Alternative attaching means may comprise a locking arrangement having features that permit shaft insertion in one orientation relative to the base, and that lock the shaft in a second orientation, the respective shaft orientations being displaced from one another by an angular distance no greater than one-half turn of the shaft, and preferably no greater than one-quarter turn. Such a locking arrangement may comprise a continuous groove extending along the sidewall of the base member aperture, and a stud projecting laterally (i.e., radially) from the shaft and dimensioned and configured for slidable engagement in the groove. An entrance section of the groove extends inwardly into the base member from the mouth of the aperture, and a blind section of the groove, connected to an inner end of the entrance section, extends generally outwardly toward the aperture mouth but terminates short thereof; the groove may, for example, advantageously be of generally J-shaped configuration.